upper right - effect phases (each phase can set its own change envelopes for effect parameters)

bottom - envelopes and their keys in a time graph

you can drag parameters from the tree view in here to add envelopes to them; add new keys with the pencil/clipboard icon; move keys with the move icon; enter precise values with the edit boxes below; pan around with the middle button; zoom in/out with the mousewheel.

WARNING - this window sometimes gets 'stuck' in its sizing mode, as if you were holding Alt (especially after Alt-Tabbing out and back). If your mouse keeps resizing the graph instead of adding keys or selecting with a rectangular area, hit and releast Alt once or twice. The same goes for the phases window.

Let's get cracking.

Create a new effect (File - New - WootFX Effect)

In the tree view right-click and Add new element - Emitter

In the preview panel click the camera, get the effect rolling (it's not going to show up at this time yet)

Expand the emitter's properties and set:

Birth Rate: 5 - here come puffs of rectangular smoke

Velocity: 1 - the smoke floats upwards

Blend Type: Lighten - now the smoke blends properly

Particle Rotation: 2 - now the puffs rotate

Spread: 0.1 - the smoke spreads out a bit

Now let's make a choo-choo train:

Drag Birth Rate into the panel below, an "Emitter 1.Birth Rate" entry should be created there - the smoke disappears, don't worry

In the graph window click the pencil and click in the graph area to add a key with Time:0 Value:5 (or close to that) - you'll get a new key and a red line extending out of it